Film forming chlorinated polymide-ethers and method for making same

ABSTRACT

Film forming flame resistant chlorinated polyimide ethers are provided, and a method for making them. Reaction can be effected between a dihydric phenol and dichloromaleimide or tetrachlorobismaleimide in the presence of base. Selfcondensation of dichloroimidophenols also provide valuable flame resistant polymers.

United States Patent [191 Relles et a1.

1 1 FILM FORMING CHLORINATED POLYTMIDE-ETHERS AND METHOD FOR MAKING SAME [75] Inventors: Howard M. Relles, Rexford; Robert .W. Schluenz, Latham, both of NY.

[73] Assignee: General Electric Company,

Schenectady, NY.

[22] Filed: Feb. 16, 1972 [21] Appl. No.: 226,978

[52] US. Cl... 260/47 CZ, 117/161 P, 117/161 UN, 260/32.6 N, 260/33.8 R, 260/47 UA,-260/49, 260/78 UA, 260/D1G. 24

[51 Int. Cl C08g 20/32 [58] Field of Search..'.... 260/47 CZ, 78 UA, 47 UA,

[56] References Cited UNITED STATES PATENTS 3,533,996 10/1970 Grundschober et al. 260/47 1451 June 28, 1974 3,642,712 2/1972 Sambeth et a1. 260/78 3,651,012 3/1972 Holub et a1. 260/47 3,652,715 3/1972 Holub et a1. 260/860 3,652,716 3/1972 Holub et a1. 260/860 Primary ExaminerLester L. Lee Attorney, Agent, or Firm-William A. Teoli; Joseph T. Cohen; Jerome C. Squillaro ABSTRACT 29 Claims, No Drawings 1 FILM FORMING CHLORINATED POLYIMIDE-ETHERS AND METHOD FOR MAKING SAME and mixtures thereof, where R and R are selected from arylene hydrocarbon radicals, and diorgano radicals of the formula,

R is selected from divalent hydrocarbon radicals and diogano radicals of formula (3), R is selected from C alkylene.

R is selected from monovalent hydrocarbon radicals, Y is selected from lower alkyl and halogen, and x and y are whole numbers equal to from O to 3 inclusive.

Radicals included by R and R of formula (1) are for example, phenylene, tolylene, xylylene, napthylene, anthrylene, etc., and diorgano radicals, such etc. Radicals included by R of formula (2) are for example, C alkylene radicals, such as methylene, dimethylene, trimethylene, etc, and R and R radicals as previously defined. Radicals included by R are for example, alkylene radicals, such as methylene, dimethylene, trimethylene, tertramethylene, methylidene, propylidene, etc.,

There is also provided by the present invention, a I

method for making chlorinated polyimide ethers of formula (2), which comprises,

1. effecting reaction between substantially equal molar amounts of a chlorinated bismaleimide of the formula,

' 0 o c1c- 15-001 NR'N or --o o-- 01 II I and a dihydric phenol of N ROH,

Cl C

which comprises (1) effecting the self-condensation of a chloroimidophenol of formula (6) in the presence of base, (2) recovering -a chlorinated polyimide ether from the resulting mixture of l where R is as previously defined.

Included by the dihydric phenol of formula (5 there are for example, Bispheonol-A, resorcinol, hydroquinone, ortho-dihydroxybenzene, dihydroxydiphenylsulfone, 4,4'-dihydroxy-3,3, 5,5-tetramethylbiphenyl, tetrabromo-bisphenol-A, chlorohydroquinone, etc.

Chlorinated bisimides included by formula 4, and a method for making them are described in my copending application Ser. No. 226,974, filed Feb. 16, 1972,

filed concurrently herewith. As taught in Ser. No.

226,974, a-carbon hydrogen atoms on maleic anhydride and maleimides derived therefrom, can be readily replaced with chlorine atoms without undesirable side reactions to produce the corresponding polychloro aliphatically unsaturated compounds in high yields. Reaction between maleic anhydride or maleimide derived therefrom can be effected with thionyl chloride in the presence of pyridine. The order of addition of the various reactants in forming the reaction mixture is not critical. Experience has shown that optimum results are achieved, if the aliphatically unsaturated reactant, which can be, for example, the bismaleimides such as N,N-p,p'-diphenylmethane-bismaleimide or any other bismaleimide falling within the scope of formula 4, where hydrogen atoms would be shown in place of chlorine atoms is dissolved in the thionyl chloride and the pyridine is added to the resulting solution. Thionyl chloride also can be used in less than solvent amounts,

3 provided quantities are employed which are at least sufficient to replace a-carbon hydrogen atoms of the aliphatically unsaturated reactant with chlorine atoms. If desired, excess unreacted thionyl chloride can be recovered by stripping the mixture under reduced pressure. Pyridine is employed in amounts of at least 2 moles of pyridine, per mole of aliphatic unsaturated reactant. The pyridine is recovered as pyridine hydrochloride and can be reused after neutralization and drymg.

Reaction can be achieved at ambient conditions if desired, or the reactants can be refluxed to facilitate the formation of the desired polychlorinated maleic anhydride or maleimide reaction product. Reaction times of as little as 5 mnutes or less to 1 hour or more will not be unusual, depending upon such factors as degree of agitation, the ingredients employed, conditions used, proportions of the reactants, etc. There are included for example, bis-dichloromaleimides of methylenedianiline, toluenediamine, phenylenediamine, ethylenediamine, diamonodiphenylsulfone, diaminodiphenyl ether, etc.

lmide phenols included by formula 6, are for example, N-4-hydroxyphenyl-dichloromaleimide, N-3 hydroxyphenyl-dichloromaleimide, etc. The chlorinated polyimide-ethers of formula (2), can be made by effecting contact between the chlorinated bismaleimide and the dihydric phenol in the presence of a base catalyst, and suitable organic solvent. Depending upon the nature of the reactants, ambient temperatures or heating of the reaction mixture, such as to reflux along with agitation, can be required to facilitate the production of polymer. Recovery of the chlorinated polyimide-ether can be obtained by effecting the precipitation of polymer from an acidic aqueous medium, such as a methanolic aqueous medium.

Suitable organic solvents which canbe employed are any organic solvent inert to the reactants during reaction and which the reactants are soluble and which allows for the build up of molecular weight of the resulting polymer to an intrinsic viscosity of between 0.10 to 1.00. Included by such organic solvents are for example, dimethylsulfoxide, dimethylformamide, methylene chloride, dimethylacetamide, N-methylpyrrolidone, etc. Bases which can be employed in the reaction mixture to form the chlorinated polyimide ethers are for example, alkaline earth oxides, such as calcium oxide, magnesium oxide, barium .oxide, etc.; aswell as alkaline earth hydroxides; alkali metal carbonates, such as potassium carbonate, sodium, lithium, etc. In addition, there also can be employed organic amines, such as triethyl amine, dicyclohexylmethyl amine, 1,2,2,6,6-pentamethylpiperidine, pyridine, etc. Temperatures in the range of from 25C to 65C can be employed during the polymerization. Reaction times of between 30 minutes or less to several hours or more are not unusual depending upon the nature of the reactants and such factors as degree of agitation, catalyst, solvent, etc.

Generally, the self-condensation of the chloroirnide phenols of formula 6, can be readily effected using the O (at 4 I conditions such as temperature, solvent, catalyst, which are employed for the intercondensation reaction described above for the chlorinated bismaleimide and the dihydric phenol.

After the polymerization has proceeded to a desired degree, which can be determined by removal of a titer of the reaction mixture, to determine its intrinsic viscosity of the polymer in chloroform at 25C, the reaction mixture can be poured into an aqueous acidic medium containing such solvents as methanol, tetrahydrofuran, etc. to effect the precipitation of the polymer. Recovery of polymer can be achieved by standard means, such as by filtration, decanting, centrifuging, etc. Films can be cast from solutions of polymer in dimethylformarnide and chloroform. The resulting films can be employed as flame resistant insulating coatings on various substrates. The flame resistance test employed to determine the self-extinguishing characteristics of the film forming chlorinated polyimide-ethers of the present invention was as follows:

A 1/16 inch X A inch X 6 inch sample was placed three-eighths inch above a inch bnsen burner flame for 10 seconds. Thesample was then pulled out of the flame to determine whether it ignited and for what period of time. If it burned 25 seconds or less, it was considered self-extinguishing. An average of 3 film samples were employed in each test to determine the selfextinguishing characteristics of the film.

It has been found that the thermoplastic film which is cast can be rendered thermoset or insoluble in organic solvents by heating it to temperatures in the range of from 200C to 300C over a period of several v minutes. Films made in accordance with the practice of the present invention from the chlorinated polyimideethers can have tensile strength in the range of from 8,000 psi to 13,000 psi, while exhibiting elongations in the range of from between 4 to 94 percent, on an lnstron Tester at 25C.

In order that those skilled in the art will be better able to practice the present invention, the following examples are given by way of illustration and not by way of limitation.

EXAMPLE 1 cosity in dimethylformamide of 0.54 at 25C and a Tg of 173C. Based on the method of preparation, its N.M.R., l.R., spectra, and elemental analysis, the product was a polymer consisting essentially of chemically combined units of the formula,

lies, 4. ,l M 0 A flexible film of the above polymer was cast from chloroform.lt had a tensile strength of 8830 psi and a yield strength'of 91 psi and an elongation of 94 percent. The film was found to be self-extinguishing when tested in the previously described flame test.

Following the same procedure, with the exception of using 0.002 mole of dicyclohexylmethyl amine in combination with the calcium oxide in the mixture and stirring the mixture at 45C for 11 hours, there was obtained a polymer having an intrinsic of 0.55 in chloroform at C. When the calcium oxide was replaced with potassium carbonate in the above mixture, there was obtained after 7 hours at 25 a polymer having an intrinsic viscosity of 0.47 in chloroform at 25C and a yield of 81 percent.

A 61 percent yield of polymer having an intrinsic of 0.33 in chloroform at 25C was obtained after 1 /2 hours of reaction at 25 when dimethylsulfoxide was substituted for dimethylformamide and 0.0004 mole of triethylamine was added to the potassium carbonate used as base.

Both of the above polymers were cast to form valuable flame resistant films following the above described procedure.

EXAMPLE 2 I A mixture of 0.01 mole of the bis-dichloromaleimide of Example 1, 0.01 mole of hydroquinone, 0.1 mole of calcium oxide, and 0.0005 mole of triethylamide was where n is an integer which can have a value of from 10 to 500inclusive.

A film of the above polymer was cast from dimethylformamide. It had a tensile strength of l 1400 i 700 psi, and an elongation of 5 percent.

A similar procedure was repeated as described above, except that potassium carbonate was utilized in place of the calcium oxide, and there was employed 0.004 mole of triethylamine. After 7 hours of stirring at 25C, there was obtained after precipitation from the methanolic acidic media, an 86 percent yield of poly mer having an intrinsic viscosity of 0.65 when measured in cresol at 25C.

EXAMPLE3 A solution of 0.01 mole of the bis-dichloromaleimide of oxydianiline and 0.01 mole of 4,4-dihydroxy-2,2, 6.6-tetrabr0mo-3 .3 5-5 -tetramethylbiphenyl was stirred in 50 ml of dimethyl formamide at 25C. There was then added 0.1 mole of calcium oxide to the mixture while it was stirring. After 35 minutes. The mixture was too viscous to be stirred and an'additional 200 ml of dimethylformamide was added while it was stirred vigorously. There was obtained a 92 percent yield of product in accordance with the recovery work up procedure as previously described, which had an intrinsic viscosity of 0.75 in dimethylformamide in 25C. Based on the method of preparation, its IR. spectrum, and elemental analysis, the product was a chlorinated polyimide-ether consisting essentially of chemically combined units of the formula,

CH1 Br Br CH:

C-O I CH; Br Br CH; J

where n is an integer which can have a value of from 10 to 500 inclusive.

A film was cast from a dimethylformamide solution of the above polymer. lt exhibited valuable insulating and'flame resistant properties basedon the previouslydescribed test procedure.

EXAMPLE 4 Several chlorinated polyimide-ether polymerswere prepared by effecting reaction between 0.01 mole chlorinated bismaleimide of Example 1, and 0.01 mole of various bisphenols utilizing 50 ml of dimethylformamide in the respective mixtures. The polymers were prepared at 25C employing various reaction times. The following table shows the bisphenols utilized to form the respective chlorinated polyimide-ethers and the base catalyst employed in the respective mixtures, as well as the reaction time and the yield of polymer.

(Hegel TABLE 1 BlSPHENOL BASE(moles) REACTION YIELD OF TlME(hrs.) POLYMER(%) Catec hol H CaO (0.1 26

- Et N (0.00005) Bisphenol of K CO (0.1 2 90 Example 3 Tetrabromo-bis- K CO (0.1) i 85 phenol-A Et N (0.0004) Tetrachloro- K CO (0.1 5/6 84 bisphenol-A Et N (0.0004) Tetramethyl- K CO (0.1 20 81 bisphenoLA Et N (0.0004) Chlorohydro- CaO (0.1 3 A 70 quinone Et N (0.00005) EXAMPLE An additional variety of chlorinated polyimideethers were made employing the bis-dichloromaleimide of mphenylenediamine as the chlorinated bismaleimide, which was reacted with a variety of bisphenols employing 0.01 mole each of polymer reactants respectively, and utilizing 50 ml of dimethylformamide solvent and a temperature of 25C. the following shows the bisphenols employed, as well as the base and moles, reaction time and the yield of the respective polymers:

The above chlorinated polyimide-ethers werecast from dimethylformamide solvent to produce high strength flame resistant films exhibiting valuable insulating characteristics.

EXAMPLE 6 A further variety of chlorinated polyimide-ethers were prepared by effecting reaction between 0.01 mole of the bis-dichloromaleimide of p-phenylenediamine with an equal molar amount of various bisphenols utilizing 50 ml of dimethylformamide at a temperature of 25C. The following shows the base and moles utilized in the reaction as well as the reaction time and yield of polymer: I

TABLE lV-Continu ed BIS-DICHLORO- BASE(moles) REACTION YIELD OF MALEIMIDE OF TlME(hrs.) Polymer (7c) sulfone Et N (0.00005) -2,4-toluene- CaO (0.1 3 87 diamine Et N (0.00005) -Oxydianiline CaO (0.1) 32.5 94

Et N (0.00005) The above chlorinated polyimide-ethers were recovered in accordance with the above described procedure and cast from dimethylformamide. There were obtained flame resistant tough films exhibiting valuable insulating characteristics.

EXAMPLE 8 A reaction was effected between equal molar amounts of the bis-dichloromaleimide of ethylene diamine and the bisphenol of Example 3 in the presence of calcium oxide and utilizing a dimethyl formamide as a solvent. Reaction was effected at 25C in about 4 /2 hours, during which time the mixture was stirred constantly. There was obtained a 90 percent yield of polymer hav-. ing an intrinsic viscosity of 0.12 in dimethylformamide at 25C following the previously described procedure TABLE III BISPHENOL BASE(moles) REACTION YIELD OF TlME(hrs.) POLYMER(%) Bisphenol-A K CO (0.1) I 77 Et N (0.0004) Tetrachloro- CaO (0.l) 22 72 hisphenol-A Et N (0.00005) Films were cast from dimethylformamide.solutions of each of the above polymers. All were found to be selfextinguishing.

EXAMPLE '7 A number of chlorinated polyimide-ethers were prepared utilizing 0.01 mole of Bisphenol-A with an equal molar amount of various bis-dichloromaleimides in ml of dimethylformamide and employing a temperature of25C, with stirring. The chlorinated bisimides employed, the base in moles and reaction time, and yield of respective chlorinated polyimide-ethers are shown as follows.

TABLE IV BlS-DICHLORO- BASE(moles) REACTION YIELD OF MALEIMIDE OF TlME(hrs.) Polymer Diaminodiphenyl CaO (0.1) 4.50 98 for recovery.

Based on the method of preparation, its I. R. spectrum, and elemental analysis, the polymer consisted essentially of chemically combined units of the formula,

CH; Br Br Ha, I

ca Br Br ole-i EXAMPLE 9 Reaction was effected between 0.01 mole of the bisdichloromaleimide of 1,3-propylenediamine and 0.01 mole of various dihydric phenols in the presence of a base catalyst and dimethylformamide. The reaction was conducted at 25C during which time the mixture was constantly stirred. The following shows the dihydric phenols employed and the base utilized, as well as the yield of polymer obtained in both instances:

DIHYDRIC PHENOL BASE YIELD OF POLYMER Bisphenol-A CaO triethylamine 87 Bisphenol of CaO .95 Example 3 EXAMPLE 10 A sample of 0.01 mole of N-(3-hydroxyphenyl)- dichloromaleimide was stirred for a period of 5 hours at 25C in 25 ml of dimethylformamide with a mixture of 0.05 mole of potassium carbonate and 0.0002 mole of triethylamine. A product was recovered by precipi tation in acidic methanolic'media and at a yieldof about 70 percent. Based on the method of preparation and infrared spectrum, it was a polymer having an intrinsic viscosity of 0.25 in dimethylformamide and consisting essentially of chemically combined units of the where n is an integer having a value of from to 500 inclusive.

Although the above examples include several of the very many chlorinated polyimide-ethers which can be made by the method of the present invention, it should be understood that the present invention is directed to a much broader class of polymers as shown by formula (l) and (2).

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A film forming chlorinated polyimide-ether conv sisting essentially of chemically combined units of the formula,

L l .l

were R is selected from arylene hydrocarbon radicals 3 and diorgano radicals of the formula,

R is selected from C alkylene and o R -Li-, -o-, and --Si l L R is selected from monovalent hydrocarbon radicals, Y is selected from lower alkyl and halogen, and x and y are whole numbers 'equalto from 0 to 3 inclusive.

2. A chlorinated 'polyimide-ether consisting essentially of chemically combined units of the formula where R is selected from arylene hydrocarbon radicals, and diorgano radicals of the formula (Y) x (Y) r and R is selected from divalenthydrocarbon radicals and said diorgano radicals, R is selected from C alkylene.

R is selected from monovalent hydrocarbon radicals,

Y is selected from lower alkyl and halogen, and .r and y are whole number equal to from 0 to 3 inclusive.

3. A method for making a chlorinated polyimideether which comprises, (1) effecting the selfcondensation at a temperature in the range of from 25C 65C of a dichloromaleimido-phenol of the for- 4 in the presence of base, selected from the class consisting of alkaline earth oxides, alkaline earth carbonates, alkaline earth hydroxides, and organic amines, and (2) pouring the resulting reaction mixture into an aqueous acidic medium and (3) recovering a chlorinated polyimide-ether from the mixture of l), where R is selected from arylene hydrocarbon radicals, and diorgano radicals of the formula,

R is selected from C(14) alkylene,

R is selected from monovalent hydrocarbon radicals, J

Y is selected from lower alkyl and halogen, and x and y are whole numbers equal to from 0 to 3 inclusive.

4. A chlorinated polyimide-ether in accordance with claim 1, where R is i 5. A chlorinatedpolyimide-ether in accordance with claim 1, where R is v 1 1 6 A chlorinated polyimide-ether in accordance with claim 2, where R is 7. A chlorinated polyimide-ether in accordance with claim 6, where R is i 8. A chlorinated polyimide-ether in accordance with claim 6, where R is 9. A chlorinated polyimide-etherin accordance with claim 6, where R is on, Bk Br cm I 10. A chlorinated polyimide-ether in accordance with claim 6, where R is i 11. A chlorinated polyimide-ether in accordance with claim 6, where R is r Br- CHI 1' r' l 12. A chlorinated polyimide-ether in accordance with claim 6, where R is {fig 14. A chlorinated polyimide-ether in Y with claim 6, where R is i 3 CH3 CH3 L dZH;

15. A chlorinated polyimide-ether in with claim 2, where R is v with claim 15, where R is 16. A chlorinated polyimide-ether in accordance accordance accordance I I v 17. A chlorinated polyimide-ether in with claim 15, where R is 18. A chlorinated polyimide-ether in with claim 15, where R is CH; B! B! UB3 19. A chlorinated polyimide-ether in with claim 15, where R is Cl C1 CH:

.. l c c 7.

I 20. A chlorinated polyimide-ether in with claim 15, where R is accordance accordance "accordance accordance a i 13 21. A Chlorinated polyimide-ether in .with claim 2, where R is 22. A chlorinated polyimide-ether in with claim 21, where R is 23. chlorinated polyimide-ether inwith claim 21, where R is t 24. A chlorinated polyimide-ether in with claim 21, where R is 25. A chlorinated .polyimide-ether in with claim 2. where R is CH; Br Br CH:

. 26. A chlorinated polyimide-ethe'r in with claim 25, whereR is accordance accordance accordance accordance accordance O GIG-1 -CIC ll NR N h Cl -C C- Cl I and a dihydric phenol of the formula,

[HORAOH] noa on in the presence of base, selected from the class consistaccordance ing of alkaline earth oxides,-alkaline earth hydroxides, alkaline earth carbonates and organic amines, and (2) pouring the resulting reaction mixture into an aqueous acidic medium and (3) recovering a chlorinated polyimide-etherfrom the resulting mixture of l) where R is selected from arylene hydrocarbon radicals, and diorganoradicals of the formula,

R is selected from divalent hydrocarbon radicals and said diorgano radicals, R is selected from. C alkylene, v

R is selected from monovalent hydrocarbon radicals, Y is selected from lower alkyl and halogen, and x and y are whole numbers equal to from 0 to 3 inclusive. 

2. A chlorinated polyimide-ether consisting essentially of chemically combined units of the formula
 3. A method for making a chlorinated polyimide-ether which comprises, (1) effecting the self-condensation at a temperature in the range of frOm 25*C - 65*C of a dichloromaleimido-phenol of the formula,
 4. A chlorinated polyimide-ether in accordance with claim 1, where R is
 5. A chlorinated polyimide-ether in accordance with claim 1, where R is
 6. A chlorinated polyimide-ether in accordance with claim 2, where R2 is
 7. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 8. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 9. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 10. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 11. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 12. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 13. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 14. A chlorinated polyimide-ether in accordance with claim 6, where R1 is
 15. A chlorinated polyimide-ether in accordance with claim 2, where R2 is
 16. A chlorinated polyimide-ether in accordance with claim 15, where R1 is
 17. A chlorinated polyimide-ether in accordance with claim 15, where R1 is
 18. A chlorinated polyimide-ether in accordance with claim 15, where R1 is
 19. A chlorinated polyimide-ether in accordance with claim 15, where R1 is
 20. A chlorinated polyimide-ether in accordance with claim 15, where R1 is
 21. A chlorinated polyimide-ether in accordance with claim 2, where R1 is
 22. A chlorinated polyimide-ether in accordance with claim 21, where R2 is
 23. A chlorinated polyimide-ether in accordance with claim 21, where R2 is
 24. A chlorinated polyimide-ether in accordance with claim 21, where R2 is
 25. A chlorinated polyimide-ether in accordance with claim 2, where R1 is
 26. A chlorinated polyimide-ether in accordance with claim 25, where R2 is
 27. A chlorinated polyimide-ether in accordace with claim 25, where R2 is -CH2CH2-.
 28. A chlorinated polyimide-ether in accordance with claim 25, where R2 is -CH2CH2CH2-.
 29. A method for making a chlorinated polyimide-ether which comprises, (1) effecting reaction at a temperature between about 25*C - 65*C between equal molar amounts of a bis-dichloromaleimide of the formula, 